Farm tractors typically include one or two power take-off shafts extending rearwardly from a vertical wall of the tractor in a position to engage the drive shaft of a trailing implement. Safety shields are provided as regular equipment on such tractors to protect the operator from inadvertent contact with a rotating power take-off shaft or the portion of a drive shaft attached to the power take-off shaft or immediately adjacent thereto.
While such shields serve the intended function, they also make the power take-off shaft or shafts less accessible to the point that they are often considered "in the way" during attachment and detachment of a trailing implement with the tractor and its power take-off shaft. Power take-off shaft shields often have the further disadvantage of shielding the shafts from the view of the operator. Such shields are frequently removed and discarded, with the obvious attendant disadvantages.
In the prior art, there have been various attempts to make shields which may be removed or adjusted temporarily to accommodate the attachment or detachment of trailing implements. Among such shields of the prior art are those disclosed in the following U.S. Pat. Nos.:
4,442,742 (Hartman) PA1 Re. 30,152 (Davis) PA1 3,733,854 (Young et al.) PA1 3,504,508 (Bornzin) PA1 3,389,763 (Meinert) PA1 2,967,432 (Du shane et al.) PA1 2,858,680 (Harrington) PA1 2,696,089 (Heth) PA1 2,618,980 (Cook) PA1 2,410,503 (Johnson)
Certain adjustable shield assemblies may be tilted upwardly for the purpose of making the power take-off shafts more readily accessible for attachment and detachment of implements. Such tilting shield assemblies do not make the power take-off shafts sufficiently accessible. Operators, who stand beside the power take-off shafts and the shield assemblies during attachment and detachment of implements, tend to be in a position requiring them to look down on such equipment. Tilting of the shield assembly usually does little to improve accessibility and visibility of the power take-off shafts from that vantage point.
Despite various prior improvements, power take-off shaft shields are still considered, by those who use such equipment in the field, to be the cause of substantial accessibility and visibility problems during attachment and detachment of trailing implements. It is to the solution of these problems that this invention is addressed.